1. Field of the Invention
This invention relates in general to communications processing systems, and more particularly to digital signal processor (xe2x80x9cDSPxe2x80x9d) based communications cards.
2. Description of the Prior Art
This application deals with technology related to that in U.S. patent application Ser. No. 08/944,209, filed on Oct. 6, 1997, now U.S. Pat. No. 5,968,158. That application is entitled xe2x80x9cA DSP-based, Multi-bus, Multiplexing Communications Adapter,xe2x80x9d has a common assignee with the present invention, and its disclosure is incorporated herein by reference. That co-pending application describes a pair of communications adapters, which each includes a number of DSPs and network interface circuits for the attachment of a multi-channel telephone line. A bus connecting the communications adapters can carry data between a network line attached to one of the adapters and the DSPs of the other adapter. The DSPs on each card are connected to a host, or controller, processor. Each DSP interrupts its host processor by transmitting an interrupt control block as data to a data memory of the host processor, and by subsequently sending an interrupt causing the host processor to examine the data memory. Preferably, the interrupt control block includes data representing a number of requested interrupts.
This application deals with technology that is also related to that in U.S. patent application Ser. No. 08/979,531, filed Nov. 26, 1997, now U.S. Pat. No. 6,178,180. That application is entitled xe2x80x9cCommunications Adapter for Processing ATM and ISDN Data,xe2x80x9d has a common assignee with the present invention, and its disclosure is incorporated herein by reference. That co-pending application describes a pair of communications adapters, which each include a network interface and a signal processing means. Each adapter can process data in either integrated Services Digital Network (xe2x80x9cISDNxe2x80x9d) format or Asynchronous Transfer Mode (xe2x80x9cATMxe2x80x9d) format. Each signal processing means preferably includes a pair of DSPs.
In the known prior art, DSP Adapters for communications applications, such as for telephone communications, typically have utilized custom hardware and firmware that may require significant modifications in hardware and firmware to implement changes in communication protocols, data types, and other changes in operational parameters. Interfaces to these DSP Adapters have not been very flexible to adapt to these changes as may be necessary for new applications.
Accordingly, there is a need for a method and apparatus for increasing the flexibility of interfaces of DSP Adapters for varying applications and for overcoming the limitations in the prior art.